Functional anatomy of idiomatic expressions.

Idiomatic expressions (IE) are groups of words whose meaning is different from the sum of its components. Neural mechanisms underlying their processing are still debated, especially regarding lateralization, main structures involved, and whether this neural network is independent from the spoken language. To investigate the neural correlates of IE processing in healthy Spanish speakers.Twenty one native speakers of Spanish were asked to select one of 4 possible meanings for IE or literal sentences. fMRI scans were performed in a 3.0T scanner and processed by SPM 12 comparing IE vs. literal sentences. Laterality indices were calculated at the group level. IE activated a bilateral, slightly right-sided network comprising the pars triangularis and areas 9 and 10. In the left hemisphere (LH): the pars orbitalis, superior frontal, angular and fusiform gyrus. In the right hemisphere (RH): anterior insula, middle frontal, and superior temporal gyrus. This network reveals the importance of the RH, besides traditional LH areas, to comprehend IE. This agrees with the semantic coding model: the LH activates narrow semantic fields choosing one single meaning and ignoring others, and the RH detects distant semantic relationships, activating diffuse semantic fields. It is also in line with the configuration hypothesis: both meanings, literal and figurative, are executed simultaneously, until the literal meaning is definitively rejected and the figurative one is accepted. Processing IE requires the activation of fronto-temporal networks in both hemispheres. The results concur with previous studies in other languages, so these networks are independent from the spoken language. Understanding these mechanisms sheds light on IE processing difficulties in different clinical populations and must be considered when planning resective surgery.

Argentine Registry of neurological manifestations due to coronavirus-19 (COVID-19)

COVID-19 disease has spread around the world since December 2019. Neurological symptoms are part of its clinical spectrum. ObjectiveTo know the neurological manifestations in patients infected by COVID-19 in Argentina. MethodsMulticenter study conducted in adults, from May 2020 to January 2021, with confirmed COVID-19 and neurological symptoms. Demographic variables, existence of systemic or neurological comorbidities, the form of onset of the infection, alteration in complementary studies and the degree of severity of neurological symptoms were recorded. Results817 patients from all over the country were included, 52% male, mean age 38 years, most of them without comorbidities or previous neurological pathology. The first symptom of the infection was neurological in 56.2% of the cases, predominantly headache (69%), then anosmia / ageusia (66%). Myalgias (52%), allodynia / hyperalgesia (18%), and asthenia (6%) were also reported. 3.2% showed diffuse CNS involvement such as encephalopathy or seizures. 1.7% had cerebrovascular complications. Sleep disorders were observed in 3.2%. 6 patients were reported with Guillain Barre (GBS), peripheral neuropathy (3.4%), tongue paresthesia (0.6%), hearing loss (0.4%), plexopathy (0.3%). The severity of neurological symptoms was correlated with age and the existence of comorbidities. ConclusionsOur results, similar to those of other countries, show two types of neurological symptoms associated with COVID-19: some potentially disabling or fatal such as GBS or encephalitis, and others less devastating, but more frequent such as headache or anosmia that demand increasingly long-term care.